An Etymological Dictionary of Astronomy and Astrophysics

The Great Bear. An extensive and prominent constellation in the region of the north celestial pole, at approximately 10h 40m right ascension, +56° declination. The seven brightest stars of Ursa Major are known as the → Big Dipper. The region contains the planetary → Owl Nebula and the spiral galaxies M81 and M82. Abbreviation: UMa, Genitive: Ursae Majoris.

Etymology (EN): Ursa,from L. ursus “bear,” cognate with Pers. xers, as below; Major irregular comparative adj. of magnus “large, great,” cognate with Pers. meh “great, large” (Mid.Pers. meh, mas; Av. maz-, masan-, mazant- “great, important,” mazan- “greatness, majesty,” mazišta- “greatest;” cf. Skt. mah-, mahant-; Gk. megas; PIE *meg- “great”).

In Gk. mythology, Zeus falls in love with the nymph Callisto, and they have a son named Arcus. To hide Callisto from the wrath of his wife, Hera, Zeus changed her into a bear. Later on, when Arcus saw the bear Callisto, drew his bow and prepared to shoot her.
To prevent Arcus from killing his mother, Zeus placed them together in the sky as the Big Bear and the Little Bear.

Etymology (PE): Xers “bear,” dialectal Tabari aš;
Mid.Pers. xirs, Av. arša- “bear;” cf. Skt. rksa- “bear;” Gk. arktos; L. ursus; PIE base *rtko- “bear;” bozorg “large, magnificient, great;” Mid.Pers. vazurg “great, big, high, lofty;” O.Pers. vazarka- “great;” Av. vazra- “club, mace” (Mod.Pers. gorz “mace”); cf. Skt. vájra- “(Indra’s) thunderbolt,” vaja- “strength, speed;” L. vigere “be lively, thrive,” velox “fast, lively,” vegere “to enliven,” vigil “watchful, awake;”
P.Gmc. *waken (Du. waken; O.H.G. wahhen; Ger. wachen “to be awake;” E. wake); PIE base *weg- “to be strong, be lively.”